A conventional passenger aircraft includes a fuselage, a cabin interior attached to and/or supported by the fuselage, and thermal/acoustic insulation bags or pieces in the fuselage frame bays between the fuselage frames. For further cabin noise reduction, an additional sound-deadening blanket can be added between the fuselage structure and the cabin liner. As the aircraft is flown, the fuselage interacts with the atmosphere. This interaction generates vibration which, if left unchecked, will be perceived by occupants of the aircraft as noise, which is undesirable. The sound-deadening blanket is used to suppress the transmission of noise into the cabin. The sound-deadening blanket is positioned to intercept the noise vibrations and is configured to suppress the vibrations transmitted from the fuselage towards the cabin.
Conventional sound-deadening blankets have three layers through the depth of the blanket. The three layers include a center layer of a sound barrier material surrounded by two layers of sound absorbing material. The sound absorbing layers absorb sound compression waves that bounce between the sound barrier layer and the fuselage and between the sound barrier layer and the cabin interior.
During the lifespan of the aircraft, it is often desirable to access electronic components, electrical wires, oxygen lines, or the like that are located between the fuselage and the sound-deadening blanket. Such access is often accomplished by cutting through the sound-deadening blanket. Such cuts are typically taped back together with a tape applied to the inner layer of the sound-deadening blanket. Taping the inner layer typically results in increased sound transmission as contrasted with the uncut sound-deadening blanket. Although these sound-deadening blankets are adequate for their intended purpose, the need for improved sound deadening in the cabin of the aircraft is essentially constant.
As such, it is desirable to provide sound deadening assemblies and methods that provide improved ease of assembly and ease of repair. In addition, other desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.